package org.example.day20240812;

import java.util.Scanner;

public class text3 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int num = scanner.nextInt();
        long result = 1;
        for(int i=2;i<=num;i++){
            result*=i;
        }
        System.out.println(result);
    }
}
